class_docstr: Tests for overlap matrix
docstr: Test that overlap_matrix returns the correct matrix when no differentiable parameter is
  used.
docstr_tok: ["Test","that","overlap_matrix","returns","the","correct","matrix","when","no","differentiable","parameter","is","used","."]
code: def test_overlap_matrix_nodiff(self, symbols, geometry, s_ref):
      r"""Test that overlap_matrix returns the correct matrix when no differentiable parameter is
      used."""
      mol = qchem.Molecule(symbols, geometry)
      s = qchem.overlap_matrix(mol.basis_set)()
      assert np.allclose(s, s_ref)
  
imports: import pytest
  import pennylane
  from pennylane import numpy
  from pennylane import qchem
label_desc: Use image node_id 2 for calling the TestOverlapMat obj's underlying member method code with example usage: obj.test_overlap_matrix_nodiff(symbols, geometry, s_ref) without return types